From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Twelve points on the mechanics and potential improvements for the 'V' Series steering.
| Identifier | ExFiles\Box 180\M3\M3.5\ img018 | |
| Date | 15th April 1925 | |
| TO DAY & HS.{Lord Ernest Hives - Chair} FROM R.{Sir Henry Royce} SECRET. R CLASSIC R4/M15.4.25. C-c to CJ. RJ. PN.{Mr Northey} GWB. S-c to RG.{Mr Rowledge} RY. 'V' SERIES STEERING. Y8430 4214 (1) One must realise that any departure from vertical pivots centre point steering must make the steering heavier and more vigorously self righting (because there is greater lift). We have done this. (2) Any increase in weight on the front stub axles must also do the same (because there is more to lift.) We have done this. (3) Any additional friction in and about the vertical pivots must have the same effect. (This has been done.) (4) For many years we have asked and refused more irreversible steering gear, now we seem to want the most efficient steering gear. (5) Your report has given valuable confirmation that the 2 locks have different leverages. This was my reason for testing the relative movements including the effect of the cross tube: this increases with the angle of the lever shewn about 11 1/2° on Hispano. (6) Since we have a heavier car we ought to make our average leverage greater than Hispano and also it would seem that the total movement of our steering should be more than Hispano because we do not require so large a wheel movement on the R.H. lock, therefore our centre should be increased 20% over present, and this would average not much over Hispano as at every point we are faster. (7) Much of this delay has been caused by the report that EAC. steering box had much less efficiency. If this exists at all it is not much. At the same time we evidently have to make it as efficient as possible and use all the features that should do so - (a) roller and ball bearings, (b) whitemetalled but levers bolted to central disc, and with its oil retaining it should be good. (You have also the Goshawk type nut to test: this may shew slight improvement.) (8) In addition to (7) if we make the steering slower by 20% this would make us 13% slower than Hispano in centre, same at 300° R.H. lock and 20% less fast at 300° L.H. lock. At present we are everywhere faster. (9) I do not think we can re-arrange levers or rods to get any advantage towards equalising the turning effect required for the 2 locks without getting into bad mechanics. (10) The most effective way of getting this better is to lighten the load on the front axle which has to be lifted, push the road wheel over the pivot, or make the pivot as vertical as possible, even departing somewhat further from centre point steering. (11) The levers carrying the cross tube should be as near 90° as we can and dare from the stub axles to prevent the loss of leverage on the L.H. lock. (12) It appears fairly certain that this trouble is the addition of small percentages multiplied together like compound interest. R.{Sir Henry Royce} | ||